Talking about dust prevention in steel barrel production edging process (1)

Talking about dust prevention in steel barrel production edging process (1)

Yang Wenliang Xin Qiaojuan

In China's steel drum production enterprises, most of the current edging processes on the production line. The barrel grinding process is a kind of barrel welding edge treatment process. The barrel welding edge treatment is to pre-treat the seam of the barrel body seam before seam welding, the main purpose of which is to eliminate the oxide on the edge. Oil stains, etc., to facilitate seam welding; secondly, to reduce the thickness of the edge, in order to ensure the quality of the subsequent process. At present, the main process in China is to sharpen the edges, that is, to grind the weld edges with 4 to 8 sets of grinders. The barrel industry is called the edging process.

People who see the edging production with their own eyes will be shocked because the working environment here is too bad, there are deafening noises, there are diffuse flying dust, smoke and smog... The noise comes from the friction between the grinding wheel and the steel plate; Dust is the grinding wheel and the particles under the grinding of the steel plate; part of the smoke is the product of the high temperature of the binder in the grinding wheel, and part of the result is the vaporization of the oil on the surface of the steel drum at high temperature. In such a work environment, the environmental protection department often asks for rectification as soon as possible, but it has not changed much so far. Why is this happening? Because the process is very good, and does not require much investment.

So, how can we reduce the smoke of the edging process? Let us first see how the smoke is formed.

First, the generation and harm of smoke and dust

During the edging process, the air in the workshop is filled with a large amount of smoke. Smoke and dust are tiny particulate matter. Dust is a granular waste formed by the friction between the grinding wheel and the steel plate. The smoke is formed by the condensation of the oil on the steel plate and the organic matter in the grinding wheel by the frictional heat. Especially when processing the galvanized sheet, the zinc is thermally oxidized to become the zinc oxide. Harmful. After the particulate matter enters the air, the diameter of which is larger than 10 microns will settle down quickly due to gravity. Only in the air near the grinding wheel will there be a relatively stable high concentration of coarser particles, and the fine particles will be longer. Floating in the air, these particulate matter can cause the grinding wheel motor and transmission system to malfunction, causing disease in the human body. People working in a dusty environment can also affect work efficiency.

After the human body inhales particulate matter, the diseases that may be caused are pneumoconiosis, alveolitis, bronchitis, occupational asthma, metal smoke, poisoning, cancer, and the like. In addition, particulate matter can affect human lung function, and some particulate matter can also cause dermatitis and conjunctivitis.

Second, the basic dust prevention measures in the workshop

In the workshop, even if measures to control the smoke are taken, some smoke and dust will inevitably scatter. Some of the smoke that diffuses with the airflow in the working environment is deposited on the top beam, the wall surface, the surface of the equipment, and the like. After being piled up to some extent, it may fall again due to mechanical vibrations, etc., suspended in the air and spread to the breathing area of ​​workers. These floating soots are sometimes much higher than the soot concentration produced by daily operations.

In order to avoid the above situation, in the workshop with smoke, it is better to install the flowering board so that the top beam is not exposed, and there is no pipe under the ceiling, no wiring; the wall surface, the window frame, etc. should also adopt a structure that is not easy to accumulate soot. The joint between the floor and the wall should preferably have a suitable arc for cleaning.

If a lot of soot is accumulated on the floor of the workplace in a short period of time, the ground may adopt a lattice structure, and the lower portion is vacuumed by a local air suction device.

Equipment layout in the workplace is also related to smoke control. If the equipment is properly arranged and the channel size is appropriate, it is convenient to fully implement the smoke control measures. At the time of design, it is important to simplify the process system and enhance continuity to minimize dusting opportunities.

Dust-cleaning equipment and non-dusting equipment should be located in different workshops or completely isolated by partition walls to limit the spread of soot and minimize the impact on other working environments.

As far as the characteristics of the edging process are concerned, among the technologies that can achieve the same process effect, the technology that emits the least amount of smoke should be used; the economy cannot be ignored, but the direct economy should not be considered, but it should be caused by the smoke. The hazards are taken into account in the comprehensive economics to choose production technology. The following dust-proof measures can be taken in terms of production technology:

1. Choose the right raw materials

In the past, many manufacturers did not consider the harmfulness of the grinding wheel material, so that harmful substances were used. In the future, other raw materials should be used instead. The choice of this choice is that the substitute should be much less harmful than the original substance; the substitute cannot make the product quality or process effect significantly lower than the original; the production cost of using the substitute is not higher or higher than the original Not much; the supply of substitutes should be stable.

The use of silicon carbide, corundum, etc. instead of sandstone with high free silica content as a grinding wheel is a representative example of the use of substitutes.

2, sealed

If the dusting process is completely sealed, it is possible to prevent the smoke from spreading to the working environment, but it is practical to be completely sealed due to the operation. Therefore, it is generally necessary to perform partial suction on the closed cover to make the clean air outside the cover flow into the cover to prevent the dusty airflow from escaping.

In addition to sealing or semi-sealing the dusting equipment, it is also possible to confine the surrounding environment of the worker in an environment where smoke is emitted. For example, in a large number of workshops where smoke is emitted, it is difficult to take thorough measures to prevent pollution, and the worker's operation room can be sealed to send fresh air to the room.

3, automation

The use of automation or remote operation has a significant effect on the prevention of smoke and dust hazards, because the workers do not need to directly participate in the operation of emitting smoke, and can fully achieve complete sealing and dust collection. However, when you need to enter the inside of the equipment for maintenance, you may encounter high concentrations of dust, then use personal protective equipment.